This invention relates to a control system for positioning implements of construction vehicles and implements such as manipulators etc.
In the conventional electric-hydraulic servo systems serving as a positioning device of the kind specified, electric-hydraulic servo valves are generally employed for conducting electric-hydraulic conversion. The electric-hydraulic servo valves are however expensive in cost and are liable to cause troubles when dust etc. enters them and when they undergo vibration, and therefore their applications are restricted.